ASME IX 1

[blaqesmith]

Rounded indications are not addressed in ASME IX for Welder qualification?
ASME IX QW-191.2.3 Acceptance Criteria for Qualification Test Welds.

 

[Surachai]

In ASME IX, QW-191.2.3 is the acceptance criteria for ultrasonic examination, terminology and acceptance criteria for round indication when radiographic examination was used for performance qualification can be found in QW-191.1 and its sub paragraphs.

 

[DekDee]

K.Surachai,
Sawadee khrab.
It is an interesting question.
If you look at QW 302.2 it references QW 191 for acceptance criteria - QW 191.2.3 is included but there is no acceptance criteria for UT.
Maybe one of the other members may know why,
Cheers,
DD

 

[blaqesmith]

Mr surachi, There exist acceptance criteria for linear indications but not for rounded indications (When you use UT for welder Qualification)

 

[weldstan]

While UT is excellent for detection and measurement of linear discontinuities, it does not provide enough accuracy for determining the size of rounded discontinuities.

 

[DekDee]

Seems a strange anomaly.
If I have a test coupon riddled with porosity it would pass UT but fail RT ?
Cheers,
DD

 

[MATEGRITY2009]

Don't forget this sentence in ASME IX

"This Code contains mandatory requirements, specific
prohibitions, and nonmandatory guidance for construction
activities. The Code does not address all aspects of these
activities and those aspects which are not specifically
addressed should not be considered prohibited. The Code
is not a handbook and cannot replace education, experience,
and the use of engineering judgment"

My opinion,
Now, I have an outdate version of ASME IX, which not state any UT criteria but If we need to specific acceptane criteria for UT round indication that not addressed in ASME IX, i will refer to UT acceptane criteria of the design construction code of that equipment.

 

[MATEGRITY2009]

I got an ASME IX 2013 Ed.

Normally for UT examination it don't seperated Linear or Round indication. All of UT detection from the back reflections are called "Indication". Refer to ASME IX -UT Criteria, it cleary state that
1 Indication that have characterized as crack, LF or IP shall be rejected. (ASME Code not called a Linear indication but Indication only)

2 Indication > 3mm in length are considered relevant and must be rejected if their length exceed.....bla..bla...bla..

What is the "2" meaning?, the meaning is porosity, slag inclusion or any weld discontinuity that act as a reflector, produced an Indication and not characterized as crack, LF or IP shall be evaluation under this sentense.

 

[Surachai]

Mategrity2009,

QW-191.2.3(b) Indications exceeding 1/8 in. (3 mm.)....... They can be accepted provide that are not characterized as crack, LOF or IP.
The above sentence has not related to the acceptance criteria addressed in its sub-paragraph, but the indication exceed 3 mm. must reported as required by ASME Section IX.

I hope this will help.

 

[MATEGRITY2009]

P'Surachai,

See my question krub

QW-191.2.3(b) Indications exceeding 1/8 in. (3 mm.)....... They can be accepted provide that are not characterized as crack, LOF or IP. (I don't said that indication >3 mm must be rejeted, what i said is " Indication > 3mm in length are considered relevant and must be rejected if their length exceed sub para 1, 2 & 3)
The above sentence has not related to the acceptance criteria addressed in its sub-paragraph, but the indication exceed 3 mm. must reported as required by ASME Section IX. (Could you show ASME IX sentence related this requirement)

 

[DekDee]

Guys,
Relevant indications must be evaluated.
If they are evaluated they should be reported - no matter what the code or testing procedure.

The UT acceptance criteria states indications over 3 mm (except cracks, LOF or LOP) are relevant and therefore must be evaluated.
The RT acceptance criteria states rounded indications can be 3 mm maximum.
So a 2 mm gas pore cannot be evaluated by UT but a 6 mm long wormhole can be.

This then leads back to weldstan's statement " While UT is excellent for detection and measurement of linear discontinuities, it does not provide enough accuracy for determining the size of rounded discontinuities."

Cheers,
DD

 

[Surachai]

Mategrity2009,

Para. T-491.1 is the requirement for recording the indications as defined by QW-191.2.3(b).

I hope this help.

 

[MATEGRITY2009]

P'Surachai,

Thanks a lot krub.